<div dir="ltr">Hi Matthew! I the future we can add new function `group_to_list`:<div> </div><div> select((p, group_to_list(c)) for p in Person for c in p.cars if c.make in ("Toyota", "Honda")) This function will perform aggregation in SQL. In PostgreSQL it will be translated to `array_agg`, in Oracle to `collect`, in MySQL and SQLite to `group_concat`. Right now in your case it is necessary to perform grouping in Python: import itertools query = select((p, c) for p in Person for c in p.cars if c.make in ("Toyota", "Honda")) result = [ (person, [ car for person, car in group ]) for person, group in itertools.groupby(query, key=lambda row: row[0]) # row[0] is person ] P.S.: By the way, did you try to use db_session(strict=True)? I'm curious to know if it reduced the memory usage in your application Regards, Alexander </div></div><div class="gmail_extra"> <div class="gmail_quote">On Fri, Jul 1, 2016 at 12:57 AM, Matthew Bell <<a href="mailto:matthewrobertbell@gmail.com" target="_blank">matthewrobertbell@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><pre>Hello, if I have this query (from the docs) </pre><pre> select((p, c) for p in Person for c in p.cars if c.make in ("Toyota", "Honda"))</pre> </div>How can I have p be distinct, while c is not distinct? <pre>select((distinct(p), c) for p in Person for c in p.cars if c.make in ("Toyota", "Honda")) </pre><pre>doesn't seem to work. </pre><pre>Thanks! </pre> <div> -- <div data-smartmail="gmail_signature">Regards, Matthew Bell </div> </div></div> _______________________________________________ ponyorm-list mailing list <a href="mailto:ponyorm-list@ponyorm.org">ponyorm-list@ponyorm.org</a> <a href="/ponyorm-list" rel="noreferrer" target="_blank">/ponyorm-list</a> </blockquote></div> </div>